I tend to think(I know opinions differ on this one) that "the ship careened out of control" is a mistake for "careered", not a second meaning of careen. I appreciate that once a mistake is made often enough, dictionaries should start recognising the new meaning, even if it was originally a mistake. I would say we havent quite got to that point with careen/career yet, but I'm sure we can agree to differ on this one, Amos.
   On the other point, I am totally clear that careen can mean either to tip the boat over, or to scrape the barnacles off once you have tipped it over. This usages are long, long established. Eg " we spent a week in the bay careening the boat". It didn't take a week to tip it over.
    I'm not an amateur pedant, Amos, I'm a full-timer. My two parents, four grand-parents, and only aunt and uncle, were all school-teachers. I've got it in the blood!